The present invention relates to data communication between two terminals connected to a data communication network, such as a TCP/IP network and more specifically to the establishment of connections between a first and a second terminal, when at least the second ti is a mobile terminal.
The term xe2x80x9cmobile terminalxe2x80x9d in this document is taken to mean any lad of terminal used for data communication, which is connected to a mobile telecommunications network, such as a GSM network. The terminal may be a mobile telephone, which is connectable to a computer, such as a personal computer, or a portable computer composing a telephone unit and/or a modem.
Establishing a connection for data communication between a fixed final in a data network, such as a TCP/IP network and a mobile terminal connected to the data network via a mobile telecommunications network, or between two mobile terminals via the data network, cannot be done in the conventional way, by calling the mobile terminal.
In order for a data communication connection to be established between two computers, the computer initiating the connection must know the address of the other computer. If one of the computers is a mobile terminal, the address of this computer is not known, since a mobile terminal may move around between different Mobile Switching Centres (MSCs) and/or Base Station Controllers (BSCs).
Also, the mobile terminal receiving the call, must be able to detect that the connection requested is a data connection and not an ordinary speech connection.
A solution for sending telefax or data to a mobile telephone is known, in which a telephone is identified by a number other than its ordinary telephone number when, for example, a telefax is to be sent to the telephone. The telephone then stores the incoming data, which may be forwarded to a fax machine to be printed as a telefax, or to a personal computer (PC) or the like.
The Swedish patent specification SE 503752 describes an apparatus for receiving electronic mail to a mobile telephone. An X.9 router is connected to a storage device for receiving and storing electronic mail combined with a Short Message Service (SMS) message and an agent comprising control information which will be recognized in a mobile telephone. The storage device is connected to a gateway, which is connected to a mobile telephone exchange via a router. The gateway forwards electronic messages to a mobile station unit, which routs them to the mobile telephone. The mobile telephone may be connected to a personal computer for transmission of data in both directions.
The above mentioned patent specification however only discloses a system in which SMS is used to send e-mail to a mobile user. Other types of data connections are not considered.
European Patent Application 0 696 152 A2 discloses a mobile communications system for transmission of speech and data between two mobile terminals. The calling subscriber connects to a bridge unit in the network, which in turn handles the establishment of the connection. Such a bridge unit is a rather complex unit, and it would be advantageous if connections of the specified kind could be handled without a bridge unit.
WO 9 508 900, A1, and EP 642 284, A2 describe solutions for. connecting through a data network to a mobile communication system by means of a connecting computer. In both these documents, a virtual connection to an agent has to be established before connecting to the data network. When information concerning the mobile terminal is to be transmitted, the agent requires the mobile terminal to connect again, by an SMS message.
It is an object of tie present invention to enable the establishment of a data communication connection from ally terminal connected to a data network, such as a TCP/IP network, to a mobile terminal connected to the data network through a mobile telecommunications network, without the need for additional units such as bridges, and without the need to establish a virtual connection in the network.
It is another object of the present invention to enable the establishment of an e-mail connection between terminals connected to the Internet, at least one of the terminals being a mobile terminal.
It is yet another object of the present invention to enable the establishment of a data communication connection from a mobile terminal connected to an IP network to another mobile terminal connected to an IP network.
These objects are achieved according to the invention by a method for establishing a connection between a first terminal connected to a data communication network and a second terminal connected via a mobile telecommunications network to the sane data communication network said method comprising the steps of:
sending a connect request from the first terminal to a node in the mobile telecommunications network;
sending a signal from the node requesting the second terminal to establish a connection to the first terminal;
initiating the connection between the second terminal and the first terminal, width the second terminal as the originator;
establishing the connection between the second teal and the first terminal.
The invention offers the following advantages:
It enables the establishment of a data communication connection from any terminal, including mobile terminals, to a mobile terminal.
Only one number is needed to the mobile terminal regardless of the type of connection wanted.
It enables the transfer of any kind and any amount of data.
A dialogue between two terminals exchanging text is possible.
It might be used as a notification medium, for example the mobile terminal could connect automatically to the e-mail server and retrieve incoming e-mail, when any.